Professional Super Activated Carbon Pad, 18 Inch By 10 Inch, Options Of Nitrate, Ammonia, Phosphate Remover Pads, And Dual Bonded Pads For Fresh Water & Saltwater Aquariums, Terrariums & Hydroponics! The Professional Carbon Pad quickly reduces spikes & toxic buildup in fresh water & saltwater aquariums, aquaculture, terrariums & hydroponic systems The pad traps micro & macro organic particles, debris & excess fish food in hang-on filters, prefilter boxes, custom sumps/refugiums and more The cut to fit pad is extra thick and safe for freshwater & marine aquariums. Increases the well-being of your aquaria pets by reducing the risk of disease and stress Measures 18 inches by 10 inches